Sized paper and method of making same



Patented Jan. 12, 1932 UNITED STATES PATENT- orrlcs GEROULD '1. LANE OF ROCHESTER, NEW YORK, ASBIGNOB EASTMAN KODAK COI- PANY, OF ROCHESTER, NEW YORK, A. CORPOBATIEQN OF NEW YORK srznnurna Ann x'lrrnon OIflI AKDTGSAME fled larch 1, me.

This invention relates to a new and proved method for the manufacture of engine or beater sized paper.

. sion will on development show f0 It has hitherto been impossible to manufacture from any fiber, however purified, an engine or heater. sized paper having great durability, that is, a paper-that does not deteriorate or oxidize with age. One test or efiect of the oxidation or degeneration of the pa er is that if a sensitive photographic emulsion is left in contact with tbepaper, particularl under humid or heated COIldltlOIIS, the emu ,evidently the result of such oxidation. T is may be utilized as a measure of the oxidation. The formation and presence of considerable such fog obviously renders a paper unfit for use for photographic purposes, either as a support for sensitive layers or as a wrapping malow iodine number,

presence of an acid or acid salt w' terial for sensitive goods.

I have discovered that urified paper ulp if treated in the-beater wit a soap made In a saturated fattyacid so pure as to have a and particularly from the gh molecular wei ht, in the have pre the presence of fattyacidsof hi cipitated thereon a size in a which the fiber does not become oxidized or degenerated.

The fiber can be any cellulose of high 9.1 hacellulose content," preferably greater t an ninety per cent. Wood. pul fiber purified to the above extent gave the est results, as a greater degree of sizingwas obtained with its use.

acids capable of being saponified, whether obtained from waxes, fats, or produced synthetically by hydrogen ation of unsaturated compounds, can be used in this process if they have been freed from unsaturated compounds so that they haves iow iodine number." Fatty aeidsof higher molecular weight give the best results for sizing purposes.

For various practical reasons such as cost [may saturated fatty the most availableare palmitic steal-ic acids. The ordinary commercial acids usually include other unsaturated acids and have, therefore, a higher iodine value than five by the Beans method as described in pages in Drawing. Continuationb! application Serial in. 818,885, and November 12, 1928. This application semi g9. 848,888.

-286287 and 288 sections,17'and 18 of The Official and Tentative Methods of Analysis of the A'ssocihtion of Oflicial Agricultural Chemists, second edition, and should be purified by the eliminating of those unsaturated acids, such as oleic acid, or other easily oxidized material. Stearic acid known commercially as triple pressed stearic acid is satisfactory.

The known natural waxes include saturated and unsaturated com ounds and'when utilized for the sizing 0 papers do not protect the fibers from deterioration. However, by the removal of the unsaturated and oxidizable compounds the saturated acids of the waxes may be rendered available.

The iodine number is a measure of the extent to which the material will take up oxygen and is, therefore, a very useful determinant of the extent to which the fiber will later deteriorate or oxidize in the presence of the size.

'Itmay be noted that ordinary resin size such as is customarily used has an iodine number of or more and the paper pulp treated with it rapidly deteriorates. A. high grade white toilet soap made from mixed acids of a quality easily obtainable on the market has an iodine value of the order of 40 and gives better results but not suficiently ood for most photographic purposes or for indefinite durability. A chemically pure fatty acid would have an iodine number of zero but would. be too expensive for large scale production. A paper made with soap havin an iodine number of less than 20 wili be sta is enough for most purposes. the

number is greater than 30, the deterioration is undesirably reat. fileic acid, a very common impurity in the higher fatty acids, has

an iodine number of ninety and hence its presence in the quantity frequently found in very unde- "especially purified suiphite pulp, o extremely high alpha-cellulose content, that is over 7 is furnished in the ordinary we to the beater. One to three per cent, base on the weight of the pulp, of triple pressed commercial stearic acid is saponified with a chemically equivalent amount of caustic soda, or other alkali. This is added to the pulp in the beater and is precipitated on the fiber by sufiicient of a solution of aluminum sulphate to completely neutralize the alkalinity of the soap. The amount added would, of course, depend upon the particular acid or alkaline condition of the beater contents, such as the hardness of the water used, the

amount and alkalinity of the soap and the used instead of aluminum sulfate; particularly potassium, ammonium or chrome alum or other sulfates such as magnesium" orcopper sulfate.

Commercial stearic acid, even when pressed, still contains a considerable proportion of palmitic acid which is satisfactory for my purposes.

The product made as above described can be differentiated from-other sized papers by its non-fogging action on photographic plates or emulsions when placed in contact therewith for a long period of time under ordinary conditions or for shorter periods of time when incubated at 120? F. or above. In general, this fogging action is increased by exposure of the paper to be tested, which is, of course, unsensitized, to light prior to the test. On the subsequent developmentof the photographic plate or emulsion there is produced a fog which is a measure of, and is presumably proportional to, the oxidationor deterioration that took place in the paper during the test. This plate test is in fact a convenient and satisfactory method of measuring the useful life or lasting quality of any paper. a r V Heretofore no paper has been made for photographic or other uses, requirin a beater sized paper, that would not a ect the quality of the sensitized coating on account of the oxidation or deterioration taking place in the paper, or that would not yellow and deteriorate itself.

Paper made by my improved process and subjected to a severe test of the type outlined, results in no photographic plate and is, therefore, admirably adapted for photographic or other purposes where permanency and non-fogging qualities are pre-eminently desirable.

This process is of the utmost value from a practical standpoint for with its use a paper can be produced of the greatest durability and with no deteriorating effect when near detectible fog on the developed or in contact with sensitized photographic emulsions. Also owing to the fact that the best sizing results are obtained when this process is used with sulphite pulp, a paper can be made by this process using purified sulphite pulp of an alpha-cellulose content greater than 90% which is more durable than any beater-sized paper produced from linen or cotton or any other fiber of which-I have knowledge.

The paper produced has improved strength and flexibility, has a fine smooth surface, and high resistance to chemicals, moisture, oily substances, heat, light and combinations of these elements. Not only is it remarkably better in these qualities than sulphite or rag papers made with rosin sizing, but it is even more permanent than papers containing no beater sizing, owing to the protection afforded the fibers from air and moisture by the precipitated fatty acid. This improved sizing, being water repellant, gives greater protectionthan materials which are not water repellant or are more or less water permeable or soluble, v

such as glue, gelatine, starches or other similar materlals.

I contemplate as included in my invention all such modifications and equivalents as fall within the scope of the appended claims.

Ihis application is a continuation of my application Serial No. 318,995, filed November 12, 1928.

,Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: v c

1. In the process of making paper, the step that includes precipitating on the fibers while in a pulp condition a sizing from a soap of a saturated fatty acid containing more than nine carbon atoms and urified to an extent such that its iodine num er is less than 4:0.

2. In the process of making paper, the step that includes precipitating on the fibers while in a pulp condition a sizing from a soap of a saturated fatty acid containing more than nine carbon atoms and purified to an extent such that its iodine number is less than 20.

3. In the process of making paper, the step that includes precipitating on the fibers while in a pulp condition a sizing from a soap of a saturated fatty acid containing more than nine carbon atoms and purified to an extent such that its iodine number is less than 5.

4. In the process of making paper, the step that includes precipitating on the fibers of sulphite paper pulp having an alpha-cellulose content greater than ninety per cent, a sizing from a soap of a saturated fatty acid containing more than nine carbon atoms and purified to an extent such that its iodine number is less than 40.

5. In the process of making paper, the step that includes precipitating on the fibers of sulphite paper pulp having an alpha-cellulose content greater than ninety per cent, a sizing from a soap of a saturated fatty'acid contain-,

ing more than nine carbon atoms and purified to an extent such that its iodine number is less than 20.

6. In the process of making paper, the step that includes preci itating on the fibers of sulphite paper pulp aving an alpha-cellulose content greater than ninety per cent, a sizing from a soap of a saturated fatty acid containingmore than nine carbon atoms and purified to an extent such that its iodine number isless than 5. j

7. In the process of making paper that includessizing in the beater, the ste of adding to the paper pulp during such ating the soap of a saturated fatty acid containing more than nine carbon atoms and having an iodine number less than 40, and a precipitant for such soap.

8. In the process of making paper that includes sizing in the beater, the step of adding'to the paper pulp during such beating the soap of a saturated fatty acid containing more than nine carbon atoms and having an iodine number less than 20, and a precipitant for such soap.

9. In the process of making paper that includes sizing in the beater, the ste of adding to the paper pulp during such eating the soap of a saturated fatty acid containing more than nine carbon atoms and having an iodine number less than 5, and a precipitant for such soap.

10. In the process of making. paper that includes sizing in the beater the etc of adding to the paper pulp during such ating the soap of a higher saturated fatty acid containing more than nine carbon atoms and so free from unsaturatedcompounds that its iodine number is less than 40, and a precipitant for such soap.

11. in the process of making paper that includes sizing in the beater, the ste of adding to the paper pulp during such heating the soap of a higher saturated fatty acid containing more than nine carbon atoms and so free from unsaturated compounds that its iodine number is less than 20, and a precipitant for such soap.

12. In the process of making paper that includes sizing in the beater, the step oi adding to the aper pulp during such heating the soap 0 a higher saturated fatty acid containing more than nine carbon atoms and so free from unsaturated compounds that its iodine number is less than 5, and a precipitant for such soap.

v13. As an article of manufacture, paper comprising cellulose fibers individually coatedwith a material precipitated from the soap of a saturated fatty acid containing more than nine carbon atoms and so purified that its iodine number is less than 40.

14. As an article of manufacture, paper comprising cellulose fibers individuallycoated with a. material precipitated from the soap. of a saturated fatty acid' containing more than nine carbon atoms and so purified that its iodine number is less than 20. I

15. As an article of manufacture, paper comprising cellulose fibers individually coatedwith a material precipitated from the soap of a satuated fatty acid containin more than nine carbon atoms and so puri ed that its iodine number is less than 5.

16. As an article of manufacture, aper comprising sulfite pulp fibers indivi ually coated with a material precipitated from the soap of a saturated fatty acid containing more than nine carbon atoms and so purified that its iodine number is less than 40.

17. As an article of manufacture, paper comprising sulfite pulp fibers individually coated with a material recipitated from the soap of a saturated atty acid containing more than nine carbon atoms and so purified that its iodine number is less than 20.

18. As an article of manufacture, paper comprising sulfide pulp fibers individually coated with a material precipitated from the map of a saturated fatty acid containing more than nine carbon atoms and so purified that its iodinenumber is less than 5.

19. As an' article of manufacture, paper comprising sulfite pulp fibers having an alpha cellulose content greater than ninety per cent and individually coated with a material precipitated from the soap of a saturated fatty acid containing more than nine carbon atoms and so purified that its iodine number is less than 40.

20..As an article of manufacture, paper comprising sulfite pulp fibers havin an alpha cellulose content greater than ninety per cent and individually coated with a material precipitated from the soap of a satu-.

rated fatty acid containing more than nine carbon atoms and so purified that its iodine number is less than 20.

21. [as an article of manufacture, paper comprising sulfite pulp fibers having an alpha cellulose content greater than ninety per cent and individually coated with a material precipitated from the soap of a saturated fatty acid containingmore than nine carbon atoms and so purified that its iodine number is less than 5.

22. As article of manufacture, paper comprising sulfite pulp fibers having an alpha cellulose content greater than ninety percent and individually coated with a mate rial precipitated from the soap of asaturated fatty acid of higher molecular weight and sufiiciently free from unsaturated compoundsthat its iodine number is less than 40.

23. As an article of manufacture, paper comprising sulfite. pulp fibers having an alpha cellulose content greater than ninety per cent and individually coated with a materiaL precipitated from the soap of a saturated fatty" acid of higher molecular weight and sufliciently free from unsaturated compounds that its iodine number is less than 20.

Signed at Rochester, New York this 22nd day of Feb., 1929.

GEROULD T. LANE. 

